Moisture moderation during coal self-heating

The same coal at different moisture contents will reach thermal runaway at different times. There is also the possibility that if the coal has a sufficiently high moisture content it cannot reach thermal runaway due to the moisture moderating effects combined with the non-Arrhenius kinetics behaviour at low ambient temperatures. The moisture removal and evaporation processes that occur during coal self-heating are remodeled in this paper based on the definitions of moisture in the coal. These model projections of self-heating behavior of a specific coal in an adiabatic environment have been compared with the experimentally measured time–temperature curves of the coal. The results obtained emphasise the importance of the shape of the self-heating curve in terms of understanding the incubation behaviour of the coal that either leads to thermal runaway or continues to remain in a safe state for practical purposes.